Graphics drivers have definitely gone the other way. Those used to be in user space and aren't any more (although not in a microkernel sense, it was more of the DOS "go leave me alone and let me just poke crap into registers" sense.)

On Windows graphics drivers are now userland because historically they were the top cause of BSODs.

That's a serious problem on windows because the only people who can fix it are the authors of the driver. On Linux anyone has access to the source and can fix really bad driver bugs.

AFAIK only part of the graphics driver is in userland, with the performance critical part still in kernel space.